1. Field of the Invention
The present invention relates to a structure for arrangement of an occupant protective apparatus for a vehicle in which a bag stored in a folded state in such a manner as to extend between a front pillar and a roof side rail is inflated below the roof side rail in a vehicle compartment in the shape of a curtain by a gas ejected from an inflator during a side collision when a high load is applied to a side of the vehicle body.
2. Description of the Related Art
Conventionally, vehicle occupant protective apparatuses have already been proposed in which, in order to improve the performance of protecting the head of a vehicle occupant during a side collision, an inflator disposed in a front pillar is actuated so as to inflate a curtain-shaped air bag stored between an interior member and a body panel in such a manner as to extend between the front pillar and the roof side rail. Hereafter, a description will be given of the arrangement shown in Japanese Patent Application Laid-Open (JP-A) No. 6-227340 which discloses this type of vehicle occupant protective apparatus.
As shown in FIG. 11, a vehicle occupant protective apparatus 400 has as its main component elements a sensor 402 for detecting the state of a side collision, an inflator 404 for ejecting a gas as it is actuated upon detection of the state of the side collision by the sensor 402, and an elongated bag 412 which is arranged in such a manner as to extend from an upper end portion of a front pillar 406 along a roof side rail 408, and which is stored in a trim 410 in a folded state. Incidentally, a front end portion of the bag 412 is connected to an upper end portion of the inflator 404, and a rear end portion of the bag 412 is located at a front position of a center pillar 414.
In accordance with the above-described arrangement, when the side collision is detected by the sensor 402, the inflator 404 is actuated to eject a gas. Consequently, the ejected gas is supplied to the interior of the bag 412, and the trim 410 is deployed under the inflationary pressure of the bag 412. As a result, the bag 412 which has swollen in the shape of a curtain is interposed between the head of the vehicle occupant and the side surface of a vehicle compartment.
However, with the above-described arrangement, it is necessary to fold the bag 412 tightly in order to store the bag 412 in a narrow space between the front pillar 406 and the trim 410. For this reason, it is conceivable that the amount of energy absorption for the load in the secondary collision of the head of the occupant during a side collision of a low load (i.e., when the load of a side collision is applied to such an extent that the vehicle occupant protective apparatus 400 is not actuated) becomes insufficient if only the tightly folded bag 412 alone is used.
In relation to the invention of this application, Japanese Patent Application No. 7-187008 discloses a technique in which a buffer material, such as a hard urethane foam, a semi hard urethane foam, styrofoam, and foamed polypropylene, is disposed in a space between the roof side rail and a roof lining. Japanese Patent Application No. 7-246953 discloses a technique in which impact absorbing ribs which are made of a resin and are shaped in the form of a grid are disposed in the space between the roof side rail and the roof lining. Japanese Patent Application No. 8-119047 discloses a technique in which impact absorbing ribs which are made of a resin and are shaped in the form of a grid are disposed in a space between a front pillar inner panel and a pillar garnish.